Liners and linings for tanks and other liquid containment vessels

ABSTRACT

Exemplary embodiments are disclosed of liners, linings, and liquid containment vessels including the same. Also disclosed are exemplary method of providing liners and linings for liquid containment vessels, such as process tanks, immersion tanks, containment pits, gravity feed conduits for transferring or conveying liquid, etc. In an exemplary embodiment, a liner or lining is anchored to at least one structural component by at least one extrusion weld and at least one mechanical fastener. The mechanical fastener is coupled to the structural component. The extrusion weld is coupled to the mechanical fastener. The liner or lining may be anchored to a wide range of structural components, such as a frame, a framework, a frame member, a tank, a wall, a support member, a reinforcing member, an outer shell, a substrate (e.g., concrete, etc.) or sidewalls defining a pit or a gravity feed conduit, combinations thereof, other structures or components, etc.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 14/623,472 filed Feb. 16, 2015 (issuing as U.S. Pat. No.9,759,380 on Sep. 12, 2017), which, in turn, is a continuation-in-partof U.S. patent application Ser. No. 13/427,426 filed Mar. 22, 2012 (U.S.Pat. No. 8,955,711 issued on Feb. 17, 2015). The entire disclosures ofthe above applications are incorporated herein by reference.

FIELD

The present disclosure generally relates to liners and linings for tanksand other liquid containment vessels, such as process tanks, immersiontanks, indoor or outdoor containment pits, gravity feed conduits (e.g.,concrete trench, canal, or drain, etc.) for transferring or conveyingliquid, etc. The present disclosure also relates to tanks and otherliquid containment vessels including liners and linings, and methods ofproviding liners and linings for tanks and other liquid containmentvessels.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art and which has beenrecognized by the inventor.

Process tanks are commonly used to store contents such as acids, coatingor plating materials (e.g., chromium, black oxide, etc.) and otherchemicals. These tanks relate to immobile types that may be installedabove or below the ground, but also for the transportable types that arepart of the over-the-road semi-trailers. The tanks may also be used onor in marine vessels as well as railroad cars. The size of the tank isnot material, but the larger process tanks typically hold 1,000 gallonsor more. Moreover, process tanks are particularly adaptable for tanksintended for highly corrosive liquids, but also may be used inconjunction with other pourable materials such as grain and pellets.

Over time, process tanks may become corroded as a result of thecorrosive fluids stored therein or because of the rusting action of theexterior elements (e.g., ground water, rain, etc.). If the materialstored in a tank is corrosive, the corrosive material can contact thetank. In this situation, the life expectancy of the tank is relativelyshort and thus it becomes not only extremely expensive for replacement,but also highly dangerous for people and the environment. Furthermore,there is danger in the event that the tank will leak or rupture, orsomehow fail to retain the contents and leak the contents into theground (if the tanks are subterranean). If they are above-the-groundstorage tanks or if the tanks are over-the-road type, there is dangeralong the highways and to the passing public. Accordingly, many processtanks utilize a protective lining.

In a current lining procedure, the interior of the surface of a tank 10(FIG. 1) may first need to be prepared to receive the lining 14. Thispreparation includes surface blasting the interior of the tank 10 andsubsequent cleaning of the interior of the tank 10. With respect to thelining 14, the lining sheets 16 (FIG. 2) may be from a roll of liningmaterial. At the installation site, an adhesive may be applied to cutthe sheets 16 of lining 14. Then, the lining sheets 16 are manuallyapplied to the interior of the tank 10. As known in the art, heat may beapplied to the lining sheets 16 to assist in applying the lining sheets16 to the tank wall. Tanks typically have protrusions such as tank weldsthat bond the tank walls to the tank bottom. These tank welds protrudeinto the interior of the tank 10. Even careful placement of the sheets16 may result in gaps between the sheets 16 that are placed over theprotruding welds. In other words, the sheets 16 will lay over theprotrusions further enhancing the gaps between the sheets 16.

As shown in FIG. 2, the cutting of the lining 14 may result in unevenand/or rough edges 18 for each lining sheet 16. When the sheets 16 arebonded to the tank 10 and next to each other, the rough edges 18 of thesheets 16 do not evenly match thus resulting in gaps 20 forming betweenthe sheets 16. Even when the lining 14 is cut with relatively smoothedges 18, installation gaps 20 can still exist between the adjacentsheets 16 due to the difficult and labor intensive installation process(FIG. 3). For example, the sheets 16 are heavy and difficult to managewhen the sheets 16 are being positioned within the tight constraints ofthe process tank 10 which is a confined space with elevatedtemperatures. As such, adjacent sheets 16 may be applied in anon-uniform layout and/or with a distance between them, furtherenhancing the gaps 20 between the edges 18 of the sheets 16. Applyingthe sheets 16 at a corner of the tank 10 is particularly troublesome dueto the space and angle considerations of the corner of the tank 10.

After the lining sheets 16 are applied and adhesive attached to the tankwalls, weld strips 22 (known as a “cap over flat strip weld” or a “capover corner strip weld”) may be welded along the interfaces between eachpair of adjacent sheets 16 (FIGS. 2 and 3). The weld strips 22 may bemanually welded to the adjacent lining sheets 16. The welder used inthis process heats the weld strips 22 to the sheets 16. Similar to theapplication of the sheets 16, hand welding the weld strips 22 is alabor-intensive process. Maintaining consistent pressure with the welderis difficult since the touch of the installer applies the pressure.Additionally, it is difficult with the hand welder to maintain aconstant distance between the welding nozzle and the weld strip 22.Furthermore, the weld strip 22 may melt faster than the sheet 16, so thewelding process must be done with special care. The sheets 16 must beheated to a glossy state, yet the weld strip 22 or the sheets 16 cannotbe charred, as that would result in a failed weld.

The installer typically welds from the top of the lining sheet 16 to thebottom. As the process tank 10 may have a height such as twelve feet,this height causes starts and stops as opposed to continuous welds withtightly controlled temperatures and consistency in both pressure andtiming. In addition, welding occurs within the tight constraints of theprocess tank 10 such that the installer does not provide a constant weldover any length of time. The tedious and laborious process for stripwelding not only applies to welding strips to corner sheets, but it alsoapplies to welding strips for sheets applied to the walls of the processtank 10.

The human element of welding the strips 22 leads to weak welds(inconsistency of temperature, pressure and timing—critical variablesfor welds) and leads to voids or “pinholes” 24 within the weld thatbonds the weld strip 22 to the sheets 16 (FIG. 4). The pinholes 24 shownin FIG. 4 are exaggerated for purposes of clarity. Although the weldedstrip 22 may pass a “spark test” commonly used in the art, thesepinholes 24 lead to problems for the process tank 10. Furthermore, thecorner weld that bonds sides and the bottom of the process tank 10further exaggerates the effects of the gaps 20 and the pinholes 24 sincethe sheet 16 must position over the corner weld of the process tank 10.This corner weld or other obstacles leaves a void between the sheet 16and the tank weld.

When the tank 10 is filled with fluid 12 (FIG. 1) such as an acid, thepressure of the fluid forces the fluid 12 through the pinholes 24.Consequently, the fluid 12 forces through the gaps 20 and dispersesbetween the lining 14 and the tank 10. This leaked fluid thencorrosively attacks the tank wall. Additionally, this leaked fluid mayalso corrosively attack the bond or adhesive interface between thelining 14 and the tank wall resulting in the lining 14 pulling away fromthe tank wall. Accordingly, the gaps 20 and the pinholes 24 between thelining sheets 16 lead to adverse and dangerous conditions. When theinstaller repairs the welded strip, the heat from the repair welderdraws the leaked fluid toward the interface of the adjacent sheets 16,wherein this fluid further attacks the tank wall positioned behind therepaired weld strip.

Concrete trenches are currently used to convey or transfer corrosiveliquids (e.g., acids, chromium, black oxide phosphate, other plating andcoating materials, other chemicals, etc.). A concrete trench may begravity fed and rely solely upon gravity to transfer a corrosive liquidfrom a first location to a second location, e.g., for treatment, etc.Over time, the corrosive liquid will corrode the concrete trench, whichreduces the life expectancy of the concrete trench. If the corrosionbecomes severe enough, the corroded concrete trench may leak, rupture,or otherwise fail to retain the corrosive liquid. In which case, thecorrosive liquid may leak from the trench into the ground and ultimatelyreach groundwater.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to various aspects, exemplary embodiments are disclosedliners, linings, tanks and other liquid containment vessels includingthe same. Also disclosed are exemplary method methods of providingliners and linings for tanks and other liquid containment vessels, suchas process tanks, immersion tanks for plating or coating processes,indoor or outdoor containment pits, gravity feed conduits (e.g.,concrete trench, canal, or drain, etc.) for transferring or conveyingliquid, etc.

In exemplary embodiments, a liner or lining is anchored to a structuralcomponent by at least one extrusion weld and at least one mechanicalfastener. The mechanical fastener is coupled to the structuralcomponent. The extrusion weld is coupled to the mechanical fastener. Theliner or lining may be anchored to a wide range of structuralcomponents, such as a frame, a framework, a frame member, a tank, awall, a support member, a reinforcing member, an outer shell, asubstrate (e.g., concrete, etc.) or sidewalls defining a pit or gravityfeed conduit (e.g., trench, canal, or drain, etc.) combinations thereof,other structures or components, etc.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a front elevation view of a storage tank with a partial crosssectional view thereof illustrating a current bonded lining applied tothe tank walls, and a fluid stored therein which fluid has seepedthrough the lining and is between the tank walls and the lining;

FIG. 2 is a partial perspective view of a corner of a current liningillustrating a pair of lining sheets, a welded strip weld between thepair of lining sheets, and gaps between the lining sheets;

FIG. 3 is a partial perspective view of a corner of another currentlining illustrating a pair of lining sheets having smooth edges, awelded strip weld between the pair of lining sheets, and a gap betweenand along the length of the edges of the lining sheets;

FIG. 4 is a front perspective of the lining sheets, weld strip, and gapsshown in FIG. 3, and further illustrating pinholes formed in the weldthat bonds the weld strip to the lining sheets;

FIG. 5 is a perspective view of a liner anchored to a drywall cornerbead by extrusion welding and mechanical fasteners according to anexemplary embodiment;

FIG. 6 is a cross-sectional view of a corner of the liner shown in FIG.5, and illustrating the exemplary manner by which the extrusion weld andthus the sheets of liner material are anchored to the drywall cornerbead by screws attached to the drywall corner bead and by the extrusionweld being held or retained by the screws and washers;

FIG. 7 is a perspective view illustrating the liner shown in FIG. 5 anda wooden frame attached to the drywall corner beads at the corners ofthe liner according to an exemplary embodiment;

FIG. 8 is a perspective view of a liner anchored to a frame by extrusionwelds and mechanical fasteners according to another exemplaryembodiment;

FIG. 9 is a cross-sectional view of a corner of the liner shown in FIG.8, and illustrating the exemplary manner by which the extrusion weld andthus the sheets of liner material are anchored to the frame by rivetsattached to the frame and by the extrusion weld being held or retainedby the rivets;

FIG. 10 is another cross-sectional view of a corner of the liner shownin FIG. 8, and illustrating the exemplary manner in which extrusion weldmaterial has infused into the hollow shaft of the rivet according to anexemplary embodiment;

FIG. 11 is a partial perspective view of a liner anchored to an outershell by extrusion welds and mechanical fasteners according to anotherexemplary embodiment;

FIG. 12 is a partial perspective view of a corner of a lining anchoredto walls of a tank by extrusion welds and mechanical fasteners accordingto another exemplary embodiment, and illustrating the exemplary mannerby which the extrusion weld and thus the sheets of lining material areanchored to the tank by weld studs attached to the tank and by theextrusion weld being held or retained by the weld studs;

FIG. 13 is a partial perspective view of a corner of a lining anchoredto walls of a tank by extrusion welds and mechanical fasteners accordingto another exemplary embodiment, and illustrating the exemplary mannerby which the extrusion weld and thus the sheets of lining material areanchored to the tank by bent pins attached to the tank and by theextrusion weld being held or retained by the bent pins;

FIG. 14 is a perspective view of a bottom corner piece for a framestructure or liner (preferably one at each bottom corner) to absorbimpact if the liner is dropped to thereby provide protection against andinhibit cracking of the frame structure according to an exemplaryembodiment;

FIG. 15 is a perspective view of a liner anchored to a frame byextrusion welds and mechanical fasteners, and also including the cornerpiece shown in FIG. 14 at each of the bottom corners according to anexemplary embodiment; and

FIG. 16 is a perspective view of an example of a handle-heldextrusion-welding device that may be used in exemplary embodiments;

FIGS. 17 through 20 illustrates an exemplary embodiment of a liner orlining being anchored to a concrete substrate (e.g., concrete sidewallof a pit or a gravity feed conduit, etc.) by a screw that ismechanically fastened to the concrete substrate and by an extrusion welddisposed over and/or around at least a portion of the screw such thatthe extrusion weld is held or retained by the screw;

FIG. 21 illustrates a screw and an upper edge portion of the liner orlining shown in FIG. 20 positioned within a notched portion of theconcrete substrate;

FIG. 22 illustrates a lower half portion of a polyvinyl chloride (PVC)pipe being installed within a concrete trench according to an exemplaryembodiment;

FIG. 23 illustrates a liner or lining being anchored to the concretesidewall of the trench shown in FIG. 22 according to an exemplaryembodiment;

FIG. 24 illustrates the trench shown in FIGS. 22 and 23 after the lineror lining has been installed and anchored to the opposing concretesidewalls of the trench; and

FIG. 25 illustrates a portion of the trench, PVC pipe, and liner orlining shown in FIG. 24.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

According to various aspects, exemplary embodiments are disclosedliners, linings, tanks and other liquid containment vessels includingthe same. Also disclosed are exemplary method methods of providingliners and linings for tanks and other liquid containment vessels, suchas process tanks, immersion tanks for plating or coating processes,indoor or outdoor containment pits, gravity feed conduits (e.g.,concrete trench, canal, or drain, etc.) for transferring or conveyingliquid, etc.

In such exemplary embodiments, a liner or lining may be formed fromsheets, panels, or walls extrusion welded together by infusedthermoplastic material. Mechanical fasteners and extrusion welds anchorthe sheets to at least one or more structural components by themechanical fasteners being coupled (e.g., anchored, fastened, attached,etc.) to the structural component and the extrusion welds being coupled(e.g., anchored, held, retained, etc.) by the mechanical fasteners. Aliner or lining may be anchored in this manner to a wide range ofstructural components, such as a frame, a framework, a frame member, atank, a wall, a support member, a reinforcing member, an outer shell, asubstrate (e.g., concrete, etc.) defining a pit or gravity feed conduit(e.g., trench, canal, or drain, etc.) for transferring or conveyingliquid, combinations thereof, other structures or components, etc.

For example, an exemplary embodiment of a liner or lining includessheets, panels, or walls of lining material anchored in the corners ofthe lining to corresponding corners of a tank by extrusion welding andmechanical fasteners. The lining may be anchored to the tank by themechanical fasteners and extrusion welding such that adhesive is notneeded or used between the sheets, panels, or walls of lining materialand tank walls. In which case, failure of the non-existent orunnecessary adhesive over time or due to high temperatures is no longeran issue.

As another example, an exemplary embodiment of a liner or liningincludes sheets, panels, or walls of liner material anchored in thecorners of the liner to a frame or framework by extrusion welding andmechanical fasteners. By way of example only, the liner may be fullyassembled and anchored to the frame prior to shipping to an installationsite. At the installation site, the liner may be installed andpositioned within a tank without having to first prep (e.g., blast,grind, prime, apply adhesive, etc.) the tank's interior surface and/orwithout having to remove an existing lining, if there is one. Inaddition, exemplary embodiments of a liner may be configured as a“drop-in” free-standing liner that is positioned within a tank withoutbonding the liner to the tank's surfaces.

By way of further example, exemplary embodiments of a liner or liningmay be anchored to sidewalls (e.g., opposing vertical concretesidewalls, etc.) of a pit or to the sidewalls (e.g., opposing verticalconcrete sidewalls, etc.) of a gravity feed conduit (e.g., trench,canal, drain, etc.) that is usable for transferring or conveying liquid.The liner or lining may be anchored to the sidewalls by mechanicalfasteners (e.g., screws, etc.) and extrusion welds. The mechanicalfasteners are mechanically fastened to the sidewalls along the top edgesof the liner or lining. In some embodiments, portions of the sidewallsmay be cut or notched (e.g., a ninety-degree cut and acute angle cut,etc.). The mechanical fasteners may then be mechanically fastened to thesidewalls within cut or notched portions of the sidewalls.

The extrusion welds are disposed over and/or around at least portion ofthe mechanical fasteners such that the extrusion welds are held orretained by the mechanical fasteners. During the extrusion welding,molten thermoplastic material may be disposed or applied over the outerexposed portions of the mechanical fasteners. Some of the moltenmaterial may also infuse into hollow interior portions of the mechanicalfasteners. For example, molten material may infuse into or within thegaps between threads of a screw or bolt, the hollow center of a washer,the tool reception site or slot of a mechanical fastener (e.g., regular,clutch-drive, Torx, Robertson, Allen, or Phillips screwdriver slot,hexagonal slot, square slot, among other slots and recesses, etc.), orother hollow interior portion of a mechanical fastener, etc.

After the molten material cools and solidifies, the solidified moltenmaterial surrounding, encapsulating, and/or in contact with portions ofthe mechanical fasteners allows the mechanical fasteners to help anchor(e.g., hold, retain, etc.) the extrusion welds. In some exemplaryembodiments, batten strips (e.g., PVC batten strips, etc.) may bepositioned (e.g., mechanically fastened, etc.) over the extrusion welds.In some exemplary embodiments, a portion a pipe or tube (e.g., half of apipe made of PVC or other chemically inert material, etc.) may bepositioned within (e.g., along the bottom of, etc.) the trench, canal,drain, or gravity feed conduit. For example, half of PVC pipe may bepositioned along the bottom of a concrete trench having sidewalls towhich a liner or lining has been anchored by mechanical fasteners andextrusion welds. Liquids may then be gravity fed or flow via gravitythrough the PVC half pipe without contacting any of the concrete of thetrench.

In exemplary embodiments, the liner or lining may be anchored to thesidewalls of a concrete pit, trench, etc. without having to extend overthe upper lip or top edge of the sidewalls. The liner or lining does nothave to be attached to the floor space or work area surrounding the pitor trench. Advantageously, the liner or lining thus will not be walkedon or driven on, e.g., by a fork lift, etc. When a liner or lining isattached to a floor outside of the pit or trench, it is possible todamage the liner or lining by walking or driving a utility vehicle onit. Also, it is common to cover the open top of a concrete pit or trenchwith metal gridwork or solid panels to allow workers to walk across thepits and trenches. Because exemplary embodiments of the liners orlinings disclosed herein may be anchored to the sidewalls of a concretepit or trench, the liner or lining may still be used even though theconcrete pit or trench will be covered with metal gridwork or solidpanels.

Also disclosed are exemplary embodiments of methods relating to linersand linings for tanks and other liquid containment vessels, such asprocess tanks, immersion tanks for plating or coating processes, indooror outdoor containment pits, gravity feed conduits (e.g., concretetrench, canal, or drain, etc.) for transferring or conveying liquid,etc. For example, an exemplary embodiment of a method includes anchoringsheets, panels, or walls of a liner to at least one or more structuralcomponents (e.g., a frame, tank, outer shell, substrate, sidewalls,etc.) by extrusion welding and mechanical fasteners. The method mayinclude extrusion welding at least one pair of sheets together byinfusing molten thermoplastic material along an interface between thepair of sheets and about at least a portion of at least one mechanicalfastener coupled to at least one structural component to thereby form anextrusion weld. The extrusion weld joins the pair of sheets and iscoupled to the mechanical fastener, whereby the pair of sheets isanchored to the structural component by the mechanical fastener coupledto the structural component and the extrusion weld coupled to themechanical fastener. Accordingly, these exemplary embodiments anchor theextrusion welds and thus the sheets of liner or liner material as themechanical fasteners are anchored (e.g., fastened, coupled, etc.) to thestructural component (e.g., a frame, a framework, a tank, a framemember, a support member, a reinforcing member, an outer shell,sidewalls, a substrate (e.g., concrete, etc.) defining a pit or gravityfeed conduit (e.g., trench, canal, or drain, etc.) for transferring orconveying liquid, combinations thereof, other structures or components,etc.) and the extrusion welds are anchored (e.g., held, retained, etc.)by the mechanical fasteners.

In other exemplary embodiments, a method includes anchoring a liner orlining to the sidewalls (e.g., opposing vertical concrete sidewalls,etc.) of a pit or to the sidewalls (e.g., opposing vertical concretesidewalls, etc.) of a gravity feed conduit (e.g., trench, canal, drain,etc.) that is usable for transferring or conveying liquid. The liner orlining may be anchored to the sidewalls by mechanical fasteners (e.g.,screws, etc.) and extrusion welds. The mechanical fasteners pass throughthe liner or lining and mechanically fasten to the sidewalls of the pit.In some embodiments, the method may include cutting or notching portionsof the sidewalls (e.g., a ninety-degree cut and acute angle cut, etc.),and then mechanically fastening the mechanical fasteners through theliner or lining to the sidewalls within cut or notched portions of thesidewalls. The method also includes extrusion welding during whichmolten material is disposed or applied over the outer exposed portionsof the mechanical fasteners. Some of the molten material may also infuseinto hollow interior portions of the mechanical fasteners. For example,molten material may infuse into or within the gaps between threads of ascrew or bolt, the hollow center of a washer, the tool reception site orslot of a mechanical fastener (e.g., regular, clutch-drive, Torx,Robertson, Allen, or Phillips screwdriver slot, hexagonal slot, squareslot, among other slots and recesses, etc.), or other hollow interiorportion of a mechanical fastener, etc. After the molten material coolsand solidifies, the solidified molten material surrounding,encapsulating, and/or in contact with portions of the mechanicalfasteners allows the mechanical fasteners to help anchor (e.g., hold,retain, etc.) the extrusion welds. In some exemplary embodiments, themethod may also include positioning batten strips (e.g., PVC battenstrips, etc.) over the extrusion welds.

As disclosed herein, exemplary embodiments of liners may include sheets,panels, or walls of liner material (e.g., flexible PVC or vinylsheeting, other suitable chemically inert material, etc.) anchored to aframe or framework (e.g., drywall corner beads, wooden frame, plasticframe, rigid PVC frame, stainless steel frame, carbon steel frame,wood-plastic composite or plastic wood frame, single piece frame,multi-piece frame, tack welded and preassembled rigid PVC multi-pieceframe, etc.) by extrusion welding and mechanical fasteners (e.g.,screws, screws and washers, rivets, pins, weld studs, other fasteners oranchoring devices, etc.). In such exemplary embodiments, mechanicalfasteners are fastened to portions of the frame that are or will belocated at the corners of the liner, which corners are defined betweenor by adjacent pairs of corner sheets of liner material. The mechanicalfasteners and pairs of adjacent corner sheets are relatively positionedsuch that portions of the mechanical fastener are located within gaps,voids, beveled regions, etc. separating opposing edges of the pairs ofadjacent corner sheets prior to extrusion welding.

Depending on the particular application, the mechanical fasteners may bepositioned relative to the pairs of adjacent corner sheets before orafter being fastened to the frame or framework. Molten thermoplasticmaterial is infused along the pairs of adjacent corner sheets byextrusion welding such that molten thermoplastic material infuses withinthe gaps, voids, beveled regions, etc. between the pairs of adjacentcorner sheets. This extrusion welding also infuses molten thermoplasticmaterial over and/or around portions of the mechanical fasteners. Someof the molten thermoplastic material may also infuse into hollowinterior portions of the mechanical fasteners. For example, moltenmaterial may infuse into or within the gaps between threads of a screwor bolt, the hollow center of a washer, the tool reception site or slotof a mechanical fastener (e.g., regular, clutch-drive, Torx, Robertson,Allen, or Phillips screwdriver slot, hexagonal slot, square slot, amongother slots and recesses, etc.), etc.

After the molten thermoplastic material cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with portions of the mechanical fasteners allows themechanical fasteners to help anchor (e.g., hold, retain, etc.) theextrusion welds. Accordingly, these exemplary embodiments anchor theextrusion welds and thus the sheets of liner material in the corners asthe mechanical fasteners are anchored (e.g., fastened, etc.) to theframe or framework and the extrusion welds are anchored (e.g., held,retained, etc.) by the mechanical fasteners.

Also disclosed herein are exemplary embodiments of linings that mayinclude sheets, panels, or walls of lining material (e.g., flexible PVCor vinyl sheeting, etc.) anchored to a tank (e.g., steel tank, etc.) orother liquid containment vessel by extrusion welding and mechanicalfasteners (e.g., rivets, pins, screws, bolts, other fasteners oranchoring devices, etc.). In such exemplary embodiments, mechanicalfasteners are fastened to portions of the tank walls that are or will belocated at the corners of the lining. The mechanical fasteners and pairsof adjacent corner sheets are relatively positioned such that portionsof the mechanical fastener are located within gaps, voids, beveledregions, etc. separating opposing edges of the pairs of adjacent cornersheets prior to extrusion welding. Depending on the particularapplication, the mechanical fasteners may be positioned relative to thepairs of adjacent corner sheets before or after being fastened to thetank. Molten thermoplastic material is infused along the pairs ofadjacent corner sheets by extrusion welding such that moltenthermoplastic material infuses within the gaps, voids, beveled regions,etc. between the pairs of adjacent corner sheets. This extrusion weldingalso infuses molten thermoplastic material over and/or around portionsof the mechanical fasteners. Some of the molten material may also infuseinto hollow interior portions of the mechanical fasteners. For example,molten material may infuse into or within the gaps between threads of ascrew or bolt, the hollow center of a washer, the tool reception site orslot of a mechanical fastener (e.g., regular, clutch-drive, Torx,Robertson, Allen, or Phillips screwdriver slot, hexagonal slot, squareslot, among other slots and recesses, etc.), or other hollow interiorportion of a mechanical fastener, etc.

The infused molten thermoplastic material may penetrate the joint to thetank walls such that infused weld areas are created that help eliminatechannels, pinholes, gaps, etc. behind the weld seams, which, in turn,helps reduce the probability of leaks and helps increase the servicelife of the tank. If a leak happens, then the welds help block solutionfrom flowing behind the lining.

After the molten thermoplastic material cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with portions of the mechanical fasteners allows themechanical fasteners to help anchor (e.g., hold, retain, etc.) theextrusion welds. Accordingly, these exemplary embodiments anchor theextrusion welds and thus the sheets of lining material in the corners asthe mechanical fasteners are anchored (e.g., fastened, etc.) to the tankand the extrusion welds are anchored (e.g., held, retained, etc.) by themechanical fasteners.

Additional exemplary embodiments include liners or linings that are notfully bonded to the floors and walls of tanks as are some conventionallinings. Instead, this exemplary embodiment anchors the liner or liningalong the bottom of the tank and along upper edge portions or verticalperimeters of the tank.

With reference now to the figures, FIGS. 5 through 7 illustrate anexemplary embodiment of a liner 100 embodying one or more aspects of thepresent disclosure. As shown, the liner 100 includes sheets, panels, orwalls 104 of liner material. Drywall corner beads 108 are anchored tothe corners 110 of the liner 100 by screws 112, washers 116, andextrusion welds 120.

The corners 110 of the liner 100 are defined between or by adjacentpairs of corner sheets 104 of liner material and weld material. Prior toextrusion welding, the sheets 104 are separated by gaps or voids alongtheir edges. The sheets 104 are joined by infused welds 120 formed byextrusion welding, such that the infused welds 120 fills the gapsbetween the sheets 104 and seals the sheets 104 such that the liner 200is capable of isolating a tank from contents (e.g., contents beingstored and/or processed, etc.) within the lined tank, as the contentscontact the liner's sheet 104 instead of the tank walls.

As shown in FIG. 6, the screw 112 is attached to or screwed into thedrywall corner bead 108. Prior to extrusion welding, the screw 112 ispositioned relatively between the pairs of adjacent corner sheets 104such that at least a portion of the threaded shank of the screws 112passes through the gap or void separating opposing edges of the pairs ofadjacent corner sheets 104. The washer 116 and the head of the screw 112are within or adjacent to the gap or void between the pairs of adjacentcorner sheets 104. Depending on the particular application, the screws112 may be positioned relative to the pairs of adjacent corner sheets104 before or after the screws 112 are attached to or screwed into thedrywall corner beads 108.

Molten thermoplastic material 124 is introduced or infused along thepairs of adjacent corner sheets 104 by extrusion welding such thatmolten thermoplastic material 124 infuses within the gaps, voids,beveled regions, etc. between the pairs of adjacent corner sheets 104.This extrusion welding also introduces or infuses molten thermoplasticmaterial 124 over and/or around the washers 116 and the screws' headsand threaded shank portions as shown in FIG. 6. Accordingly, some of themolten thermoplastic material thus infuses into hollow interior centerportion of the washers 116, the hollow interior portions or gaps betweenthe threads of the screws, and the hollow interior portion or toolreception site or slot (e.g., regular, clutch-drive, Torx, Robertson,Allen, or Phillips screwdriver slot, hexagonal slot, square slot, amongother slots and recesses, etc.) in the heads of the screws.

After the molten thermoplastic material 124 cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with the screws 112 and washers 116 allows thescrews/washers to help anchor (e.g., hold, retain, etc.) the extrusionwelds 120. Accordingly, this exemplary embodiment anchors the extrusionwelds 120 and thus the sheets 104 of liner material in the corners 110as the screws 112 are anchored (e.g., fastened, etc.) to the drywallcorner beads 108 and the extrusion welds 120 are anchored (e.g., held,retained, etc.) by the screws 112 and washers 116.

The drywall corner beads 108 may be electrically-conductive (e.g.,metal, etc.) which allows pre-leak testing such as high frequency“spark” testing and/or by a testing method disclosed in U.S. Pat. Nos.7,111,497, 8,133,345, and/or U.S. Published Patent Application2012/0148805, the entire contents of which are incorporated herein byreference. Other suitable electrically-conductive means (e.g.,electrically-conductive adhesive cement, metal foil,electrically-conductive coatings, etc.) may be used between a liner anda frame in other embodiments.

In this exemplary embodiment, the drywall corner beads 108 may beconsidered as members of a frame or framework to which the liner 100 isanchored. In other exemplary embodiments, the liner 100 may be anchoredto additional or other structural components with or without the drywallcorner beads 108, such as a plastic frame, wooden frame, rigid PVCframe, stainless steel frame (e.g., frame made of stainless steel angle,etc.), carbon steel frame (e.g., frame made of carbon steel angle,etc.), wood-plastic composite or plastic wood frame, single piece frame,multi-piece frame, tack welded and preassembled rigid PVC multi-pieceframe, outer rigid PVC shell, concrete, etc.

For example, FIG. 7 illustrates an exemplary embodiment in which awooden frame 128 is attached to the drywall corner beads 108 at thecorners 110 of the liner 100. In this example, the wooden frame 128(e.g., exoskeletal frame structure, etc.) includes members or components130 externally disposed along the corners 110 and bottom edges of theliner 100. The wooden frame 128 may include a full bottom plate. Theframe members 130 along the corners 110 are attached (e.g., mechanicallyfastened via screws, etc.) to the drywall corner beads 108. Inalternative embodiment, a liner may be anchored to a structuralcomponent (e.g., an outer shell 308 (FIG. 12), etc.) which has sidewallsand a bottom wall externally disposed along the corresponding sidewallsand bottom of the liner 100.

FIGS. 8 through 10 illustrate another exemplary embodiment of a liner200 embodying one or more aspects of the present disclosure. The liner200 includes sheets, panels, or walls 204 of liner material anchored inthe corners 210 of the liner 200 to a frame or framework 208 by rivets212 and extrusion welds 220.

The corners 210 of the liner 200 are defined between or by adjacentpairs of corner sheets 204 of liner material and weld material. Prior toextrusion welding, the sheets 204 are separated by gaps or voids alongtheir edges. The sheets 204 are joined by infused welds 220 formed byextrusion welding, such that the infused welds 220 fills the gapsbetween the sheets 204 and seals the sheets 204 such that the liner 200is capable of isolating a tank from contents (e.g., contents beingstored and/or processed, etc.) within the lined tank, as the contentscontact the liner's sheet 204 instead of the tank walls.

By way of example only, the frame 208 in this exemplary embodimentcomprises a tack welded preassembled rigid PVC multi-piece frame. Inother exemplary embodiments, the frame 208 may comprise a differentlyconfigured frame such as a frame made of wood or other materialsdisclosed herein.

Prior to extrusion welding, the rivets 212 are coupled to or driven intothe frame 208. Also prior to extrusion welding, the rivets 212 arepositioned relative to pairs of adjacent corner sheets 204 such that atleast portions of the rivets' shafts pass through gaps, voids, beveledregions, etc. separating opposing edges of the pairs of adjacent cornersheets 204. As shown in FIGS. 9 and 10, the rivets' heads are alsolocated within or adjacent to the gaps, voids, beveled regions, etc.between the pairs of adjacent corner sheets. Depending on the particularapplication, the rivets 212 may be positioned relative to the pairs ofadjacent corner sheets 204 before or after being driven into andanchored to the frame 208.

Molten thermoplastic material 224 is introduced or infused along thepairs of adjacent corner sheets 204 by extrusion welding such thatmolten thermoplastic material 224 infuses within the gaps, voids,beveled regions, etc. between the pairs of adjacent corner sheets 204.This extrusion welding also introduces or infuses molten thermoplasticmaterial 224 over and/or around the rivets' heads and shaft portionsthat are within the gaps, voids, beveled regions, etc. between the pairsof adjacent corner sheets 204.

In some embodiments, the rivets 212 may have hollow shafts such thatmolten thermoplastic material 224 infuses into and within the hollowshafts of the rivets as shown in FIG. 9. The portion of the rivet 212protruding through and outwardly beyond the frame 208 as shown in FIG. 9may be removed (e.g., cut, sheared off, etc.) prior to installation in atank. If extrusion welding is performed while the liner 200 is within atank, molten thermoplastic material may flow through the hollow rivetsand reach the tank walls. In which case, molten thermoplastic materialmay then remediate and repair the tank such as by filing crevices, etc.if the tank walls are corroded.

After the molten thermoplastic material 224 cools and solidifies, thesolidified molten thermoplastic material surrounding, inside, and/or incontact with the rivets 212 allows the rivets 212 to help anchor (e.g.,hold, retain, etc.) the extrusion welds 220. Accordingly, this exemplaryembodiment anchors the extrusion welds 220 and thus the sheets 204 ofliner material in the corners 210 as the rivets 212 are anchored to(e.g., driven into, etc.) the frame 208 and the extrusion welds 220 areanchored (e.g., held, retained, etc.) by the rivets 212.

By way of further example, the liner sheets 204 and/or frame 208 may bemade from rigid polyvinylchloride, chlorinated polyvinyl chloride(CPVC), polyethylene, polypropylene, copolymer polypropylene,polyvinylidene fluoride (PVDF), Kynar® polyvinylidene fluoride (PVDF),geomembrane, ethylene interpolymer alloy (EIA), etc.Electrically-conductive material may be disposed between the linersheets 204 and frame 208, such that the electrically-conductive materialwith a ground connection allows for leak detection, permeationmonitoring, and/or spark testing.

In the exemplary embodiment shown in FIG. 8, the liner 200 is anchoredto a structural component comprising a frame 208 (e.g., exoskeletalframe structure, etc.) that has members or components 230 externallydisposed along the corners 210 of the liner 200. The frame 208 mayinclude a full bottom plate. In alternative embodiments, a liner may beanchored to structural component (e.g., an outer shell, etc.) that hassidewalls and a bottom wall externally disposed along the correspondingsidewalls and bottom of the liner.

Double sided electrically-conductive material 232 (e.g., lead oraluminum foil attached via double sided adhesive tape, etc.) is disposedbetween the liner sheets 204 and the frame 208. The tape 232 may helphold the sheets 204 in place relative to the frame 208 before the sheets204 are anchored to the frame 208 by the rivets 212 and extrusion welds220. The liner 200 may also include a pre-leak checking tab (e.g., metal“spark” test tab, etc.) such that the pre-leak checking tab andelectrically-conductive medium 232 between the liner 200 and frame 208allows pre-leak testing. The frame 208 may have a ground connection toallow for leak detection, permeation monitoring, DC spark testing, etc.In alternative embodiments, other suitable electrically-conductive means(e.g., electrically-conductive adhesive cement, metal foil, metaldrywall corner bead, etc.) may be used between a liner and a frame toallow pre-leak testing such as high frequency “spark” testing and/or bya testing method disclosed in U.S. Pat. Nos. 7,111,497, 8,133,345,and/or U.S. Published Patent Application 2012/0148805.

FIG. 11 illustrates an exemplary embodiment of a liner 300 that includessheets 304 anchored to an outer shell 308 (e.g., rigid polyvinylchloride, etc.) by mechanical fasteners 312 (e.g., rivets, etc.) andextrusion welds 320. In this example, the outer shell 308 has sidewallsand a bottom wall corresponding in size and/or shape to the interiorliner sheets 304 (e.g., flexible polyvinyl chloride, etc.). Accordingly,the exemplary embodiment illustrated in FIG. 11 may advantageouslyprovide a double barrier protection via the inner liner sheets 304 andouter shell 308, such that there is triple protection when the liner 300is within a tank.

In this exemplary embodiment shown in FIG. 11, double sidedelectrically-conductive material 332 (e.g., lead or aluminum foilattached via double sided adhesive tape, etc.) is disposed between theliner sheets 304 and the outer shell 308. The tape 332 may help hold thesheets 304 in place relative to the outer shell 308 before the sheets304 are anchored to the outer shell 308 by the rivets 312 and extrusionwelds 320. The liner 300 also includes a pre-leak checking tab 336(e.g., metal “spark” test tab, etc.) such that the pre-leak checking tab336 and electrically-conductive medium 332 between the liner 300 andouter shell 308 allows pre-leak testing. The outer shell 308 has aground connection to allow for leak detection, permeation monitoring, DCspark testing, etc. In alternative embodiments, other suitableelectrically-conductive means (e.g., electrically-conductive adhesivecement, metal foil, metal drywall corner bead, etc.) may be used betweena liner and a frame to allow pre-leak testing such as high frequency“spark” testing and/or by a testing method disclosed in U.S. Pat. Nos.7,111,497, 8,133,345, and/or U.S. Published Patent Application2012/0148805.

With continued reference to FIG. 11, a corner insert 340 (e.g., moldedtriangular insert, etc.) is extrusion welded to a corner of the liner300, which corner is formed by the pairs of adjacent corner sheets and abottom sheet. The corner insert 340 is configured (e.g., molded, etc.)to have a triangular shape. For example, the insert 340 may be generallyhollow and have a truncated triangular pyramidal configuration(triangular pyramidal frustum). Extrusion welding the insert 340 to thecorner of the liner 300 may include infusing molten thermoplasticmaterial at a predetermined distance beyond the insert 340 and along theinfused pair of sheets and bottom sheet. In this example, infusingmolten thermoplastic material comprises introducing the thermoplasticmaterial through and/or over and/or into the intersection of theassociated sheets and insert 340. Thermoplastic material is infusedunder the controlled parameters of constant pressure and constanttemperature over time to help reduce, minimize, or preferably eliminatepinholes. This welding enhances the strength of the weld between theinsert 340 and the corner of the liner 300. In an exemplary embodiment,the predetermined distance beyond the insert 340 has a range of abouttwo inches to about four inches, the thickness of the sheets may be atleast about 3/32 inches, and the thickness of the insert 340 may have arange of about 3/16 inches to about 3/8 inches. The installer may thenrepeat the welding of inserts 340 to each of the remaining corners ofthe liner 300.

Various materials may be used for the liner's sheets 304, thermoplasticmaterial 324, corner inserts 340, and outer shell 308, such as theexemplary materials referred to herein. In an exemplary embodiment, theliner's sheets 304, thermoplastic material 324, and corner inserts 340may comprise plasticized polyvinyl chloride (e.g., Koroseal® material,etc.), while the outer shell 308 comprises high-impact rigid polyvinylchloride. By way of further example, the liner sheets 304, outer shell308, and/or inserts 340 may be made from rigid polyvinylchloride,chlorinated polyvinyl chloride (CPVC), polyethylene, polypropylene,copolymer polypropylene, polyvinylidene fluoride (PVDF), Kynar®polyvinylidene fluoride (PVDF), geomembrane, ethylene interpolymer alloy(EIA), etc.

FIG. 11 also illustrates a skirt or sacrificial layer 344, which may beformed from Teflon® polytetrafluoroethylene (PTFE) or other suitablematerial. The sacrificial layer 344 may be provided towards the top ofthe liner 300 and may thus be exposed to the ambient air. Reactivesolution may then chemically attack the sacrificial layer 344 instead ofthe liner sheets 304. The skirt or sacrificial layer 344 may comprise asacrificial layer as disclosed in U.S. Published Patent Application2012/0148805 and/or U.S. Pat. No. 8,133,345. For example, thesacrificial layer 344 may comprise a polyvinylidene fluoride (PVDF)material commonly known as Kynar® PVDF. Other materials may also be usedfor the sacrificial layer and/or other means may be used for bonding thesacrificial layer to the liner 300. Depending on the particular contentsto be stored and/or processed, the liner 300 may also be used as a tankitself for storing and/or processing contents without the liner 300having to be positioned within a tank. The exemplary embodiment of theliner 300 may advantageously have a relatively long service life, solid,strong, and fewer welds as compared to conventional liners.

Depending on the particular contents to be stored and/or processed, theliner 300 may also be used as a tank itself for storing and/orprocessing contents without the liner having to be positioned within atank. The liner 300 may advantageously have a relatively long servicelife, solid, strong, and fewer welds as compared to conventional liners.

FIG. 12 illustrates an exemplary embodiment of a lining 400 embodyingone or more aspects of the present disclosure. As shown, the lining 400includes sheets, panels, or walls 404 that are anchored in the corners410 of the lining 400 to a tank 408 (e.g., steel tank, etc.) by studwelds or anchors 412 and extrusion welds 420.

The corners 410 of the lining 400 are defined between or by adjacentpairs of corner sheets 404 and weld material. Prior to extrusionwelding, the sheets 404 are separated by gaps or voids 448 along theiredges. The sheets 404 are joined by infused welds 420 formed byextrusion welding, such that the infused welds 420 fills the gaps 448between the sheets 404 and seals the sheets 404 such that the lining 400is capable of isolating the tank 408 from contents (e.g., contents beingstored and/or processed, etc.) within the lined tank 408, as thecontents contact the lining 400 instead of the tank walls 406.

Prior to extrusion welding, the stud welds or anchors 412 are coupled to(e.g., welded via a capacitive discharge stud welder, etc.) cornerportions of the tank walls 406 corresponding to the corners 410 of thelining 400. Also prior to extrusion welding, the stud welds 412 may bepositioned relative to the pairs of adjacent corner sheets 404 such thatportions (e.g., shaft, head, etc.) of the stud welds 412 are locatedwithin the gaps or voids 448 separating opposing edges of the pairs ofadjacent corner sheets 404.

Molten thermoplastic material 424 is introduced or infused along thepairs of adjacent corner sheets 404 by extrusion welding such thatmolten thermoplastic material 424 infuses within the gaps or voids 448between the pairs of adjacent corner sheets 404. This extrusion weldingalso introduces or infuses molten thermoplastic material 424 over and/oraround portions of the stud welds 412.

After the molten thermoplastic material 424 cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with portions of the stud welds 412 allows the studwelds 412 to help anchor (e.g., hold, retain, etc.) the extrusion welds420. Accordingly, this exemplary embodiment anchors the extrusion welds420 and thus the sheets 404 of lining material in the corners 410 as thestud welds 412 are anchored (e.g., welded, etc.) to the tank 408 and theextrusion welds 420 are anchored (e.g., held, retained, etc.) by thestud welds 412.

Infused molten thermoplastic material 424 may penetrate the joint to thetank walls 406 such that infused weld areas are created that helpeliminate channels, pinholes, gaps, etc. behind the weld seams, which,in turn, helps reduce the probability of leaks and helps increase theservice life of the tank. If a leak happens, then the welds help blocksolution from flowing behind the lining 400. Accordingly, the exemplaryembodiment of the lining 400 may advantageously have a relatively longservice life, have welds that are solid and strong (more tolerable tostresses), and have fewer welds as compared to conventional linings.

FIG. 13 illustrates an exemplary embodiment of a lining 500 embodyingone or more aspects of the present disclosure. As shown, the lining 500includes sheets, panels, or walls 504 that are anchored in the corners510 of the lining 500 to a tank 508 (e.g., steel tank, etc.) by pins 512and extrusion welds 520.

The corners 510 of the lining 500 are defined between or by adjacentpairs of corner sheets 504 and weld material. Prior to extrusionwelding, the sheets 504 are separated by gaps or voids 548 along theiredges. The sheets 504 are joined by infused welds 520 formed byextrusion welding, such that the infused welds 520 fills the gaps 548between the sheets 504 and seals the sheets 504 such that the lining 500is capable of isolating the tank 508 from contents (e.g., contents beingstored and/or processed, etc.) within the lined tank 508, as thecontents contact the lining 500 instead of the tank walls 506.

Prior to extrusion welding, the pins 512 are coupled to (e.g., weldedvia a capacitive discharge stud welder, etc.) corner portions of thetank walls 506 corresponding to the corners 510 of the lining 500. Alsoprior to extrusion welding, the pins 512 may be positioned relative tothe pairs of adjacent corner sheets 504 such that portions (e.g., shaft,head, etc.) of the pins 512 are located within the gaps or voids 548separating opposing edges of the pairs of adjacent corner sheets 504.Depending on the particular configuration of the pins 512 (e.g.,straight pin without a large head, etc.), the pins 512 may be bent(e.g., at an acute angle, etc.) as shown in FIG. 13 to create a betterretention and interlock with the extrusion welds 520. For example, thepin 512 shown in FIG. 13 includes a first straight portion or shaft anda second straight portion bent at an acute angle (e.g., 30, 45, or 60degrees, etc.) relative to the shaft.

Molten thermoplastic material 524 is introduced or infused along thepairs of adjacent corner sheets 504 by extrusion welding such thatmolten thermoplastic material 524 infuses within the gaps or voids 548between the pairs of adjacent corner sheets 504. This extrusion weldingalso introduces or infuses molten thermoplastic material 524 over and/oraround portions of the pins 512, including the pins' bent portions asshown in FIG. 12.

After the molten thermoplastic material 524 cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with portions of the pins 512 allows the pins 512 tohelp anchor (e.g., hold, retain, etc.) the extrusion welds 520.Accordingly, this exemplary embodiment anchors the extrusion welds 520and thus the sheets 504 of lining material in the corners 510 as thepins 512 are anchored (e.g., welded, etc.) to the tank 508 and theextrusion welds 520 are anchored (e.g., held, retained, etc.) by thepins 512.

Infused molten thermoplastic material 524 may penetrate the joint to thetank walls 506 such that infused weld areas are created that helpeliminate channels, pinholes, gaps, etc. behind the weld seams, which,in turn, helps reduce the probability of leaks and helps increase theservice life of the tank. If a leak happens, then the welds help blocksolution from flowing behind the lining 500. Accordingly, the exemplaryembodiment of the lining 500 may advantageously have a relatively longservice life, have welds that are solid and strong (more tolerable tostresses), and have fewer welds as compared to conventional linings.

FIG. 14 illustrates an exemplary embodiment of a bottom corner piece 650that may be externally located at, disposed along, and/or define eachbottom corner of a frame structure (e.g., frame structure of a largefield erected frame liner, etc.) or a liner (e.g., a shop pre-fabricatedframe drop-in liner, etc.). The corner piece 650 may comprise moldedType II (hi-impact rigid) PVC or other suitable material for absorbingthe impact if the liner having a corner piece 650 at each corner isdropped. By way of example, the corner piece 650 may be formed viathermoforming, vacuum forming, other suitable molding process, etc.

FIG. 15 illustrates an exemplary embodiment of a liner 600 that includesthe corner piece 650 at or along each bottom corner. The liner 600includes sheets, panels, or walls 604 anchored in their corners 610 to aframe or frame structure 608 by mechanical fasteners and extrusion weldsof thermoplastic material 624. The frame 608 has members or components630 (e.g., 3 inch by 3 inch stainless or carbon steel angles, etc.)externally disposed along the corners 610 of the liner 600.

The frame 608 also includes a full bottom plate, panel, sheet, or wallin this example. By way of example, the full bottom plate may compriserigid Type II (hi-impact) PVC, and the liner material may comprisesheets of Koroseal® plasticized PVC extrusion welded together at thejoints between the sheets. This example may also include corner insertsmade of Koroseal® plasticized PVC. The frame 608 may comprise angles(e.g., 3 inch angles, etc.) framing the perimeter. The full bottom platemay be placed on top of the bottom flange of the angle framing theperimeter such that it would be locked in by sitting on top of thebottom flange of the perimeter angle. The full piece bottom may providegood protection from forklifts, etc. during shipping and handling of theliner 600 and also inhibit the forklift from cutting, gouging, etc. theliner material, for example, when the liner material is a relativelyflexible and soft material such as Koroseal® plasticized polyvinylchloride material, etc.

The corner pieces 650 may be externally disposed over the lower portionsof the frame members 630 along the corners 610 of the liner 600, suchthat the corner pieces 650 define or provide the three dimensional truebottom corners of the frame structure 608 and liner 600. The cornerpieces 650 may be coupled to the liner 600 or frame structure 608 invarious ways.

By way of example, the frame members 630 may be steel angles to whichthe corner pieces 650 are coupled to the frame structure 608. In thisexample, the steel angles are disposed under the corner pieces 650 fromboth sides. One angle is cut out to fit into the other angle. Then, oneof the angles extends upward behind the corner piece 650 and up to thevertical top corner to the top of the tank. The outer frame 608 iswelded together, and the corner pieces 650 are welded to the frame.After the liner 600 is assembled with the extrusion welds 620 anchoredto the frame 608, the extrusion welds of the liner 600 should not crackeven if the welds of the outer frame 608 should crack.

As another example, the frame members 630 may be extrusion welded at oralong the edges of the corner pieces 650. Or, for example, the cornerpieces 650 may be extrusion welded along their lower portions to edgesof the bottom plate, which may have cutouts to match the corner pieces650. The extrusion welds may be relatively flexible and have some giveso as to inhibit cracking.

In use, the corner pieces 650 provide protection against and inhibitcracking of the frame structure 608 if the liner 600 is dropped, such asfrom a forklift when the liner is being installed into a tank, etc.Accordingly, the corner pieces 650 may thus serve as underlying firm andindestructible true corner bases for the welded frame structure 608. Buteven if the welds of a frame structure did crack, the cracks in theframe structure should not significantly adversely affect theperformance of the liner as the welds of the frame structure are not inimmersion service. Plus, the liner's anchored extrusion welds and cornerinsert welds would remain uncracked and pin-hole free.

The inventor hereof has recognized that with relatively large and heavyconventional liners, it is possible that their welded joints may crackif a liner is dropped. Accordingly, the inventor has disclosed hereincorner pieces configured to provide protection against and inhibitcracking if a liner is dropped. The corner pieces may also provide afirm and flat surface for corner inserts (e.g., corner insert 340 (FIG.11), etc.).

FIGS. 17 through 21 illustrate an exemplary embodiment of a liner orlining 700 embodying one or more aspects of the present disclosure. Asshown, the liner or lining 700 is being anchored to a concrete substrate770 (e.g., opposing vertical concrete sidewalls of a pit or a gravityfeed conduit, etc.) by screws 712 and extrusion welds 720 (FIG. 20)formed by molten thermoplastic material 724 (FIGS. 17 through 19). FIG.17 shows a screw 712 mechanically fastened to the concrete substrate 770along a top edge 774 of the liner or lining 700. In this example, theconcrete substrate 770 is cut or notched (e.g., a ninety-degree cut andacute angle cut, etc.). The screws 712 are mechanically fastened orscrewed into the concrete substrate 770 within the cut or notchedportions 778. In this exemplary embodiment, holes in the concretesubstrate 770 may be formed (e.g., predrilled, etc.), and then thescrews 712 are screwed into the predrilled holes in the concretesubstrate 770. Alternative embodiments may include self-tapping screwsthat may be screwed into a substrate (e.g., plastic, wood, etc.) withoutpredrilling holes.

FIGS. 18 and 19 show an exemplary extrusion-welding device 758 beingused to introduce or infuse molten thermoplastic material 724 along thetop edge 774 of the liner or lining 700 and over the screw 712. Themolten thermoplastic material 724 may infuse along and within the gap orspace between the concrete substrate and the top edge 774 of the lineror lining 700. This extrusion welding also introduces or infuses moltenthermoplastic material 124 over and/or around the heads of the screws712 and threaded shank portions as shown by comparing FIGS. 17 through19. Accordingly, some of the molten thermoplastic material thus infusesinto hollow interior portions or gaps between the threads of the screws712, and the hollow interior portion or tool reception site or slot(e.g., regular, clutch-drive, Torx, Robertson, Allen, or Phillipsscrewdriver slot, hexagonal slot, square slot, among other slots andrecesses, etc.) in the heads of the screws 712.

After the molten thermoplastic material 724 cools and solidifies, thesolidified molten thermoplastic material surrounding, encapsulating,and/or in contact with the screws 712 allows the screws 712 to helpanchor (e.g., hold, retain, etc.) the extrusion welds. Accordingly, thisexemplary embodiment anchors the extrusion welds and thus the liner orlining 700 as the screws 112 are anchored (e.g., fastened, etc.) to theconcrete substrate 770 and the extrusion welds are anchored (e.g., held,retained, etc.) by the screws 712.

By way of example, the concrete substrate 770 may define a concrete pitor a concrete gravity feed conduit, such as a concrete trench, etc. Butother embodiments may include a liner or lining being anchored to othersubstrates besides concrete and/or other types of vessels besides pitsand trenches, such as vessels for storing, processing, transferring,and/or conveying liquids (e.g., storage or process tanks, immersiontanks for plating or coating processes, etc.). In addition, otherembodiments may use other mechanical fasteners instead of and/or inaddition to screws, e.g., washers, bolts, pins, rivets, stud welds, etc.

The liner or lining 700 may be anchored to the sidewalls of a concretepit, trench, etc. without having to extend over the upper lip or topedge of the sidewalls. For example, the liner or lining 700 does nothave to be attached to the floor space or work area surrounding a trench701 as shown in FIGS. 23-25. Advantageously, the liner or lining 700thus will not be walked on and/or driven on by utility vehicles, e.g.,fork lift, etc. When a liner or lining is attached to a floor outside ofthe pit or trench, it is possible to damage the liner or lining bywalking or driving on it. Also, it is common to cover the open top of aconcrete pit or trench with metal gridwork or solid panels to allowworkers to walk across the pits and trenches. Because the liner orlining 700 may be anchored to the sidewalls, the liner or lining 700 maystill be used even though the concrete pit or trench 701 is covered withmetal gridwork 705 as shown in FIG. 25.

As shown in FIGS. 22 through 25, a portion a pipe or tube 780 (e.g.,half of a pipe made of PVC or other chemically inert material, etc.) maybe positioned within (e.g., along the bottom of, etc.) the trench,canal, drain, or gravity feed conduit 701. For example, half of a PVCpipe 780 may be positioned along the bottom of a concrete trench 701having sidewalls 703 to which the liner or lining 700 has been anchoredby mechanical fasteners and extrusion welds as disclosed herein. Liquidsmay be gravity fed or flow via gravity through the PVC half pipe 780without contacting any of the concrete of the trench 701.

By way of example only, exemplary embodiments disclosed herein may beextrusion welded by a method and/or device as disclosed in U.S.Published Patent Application 2012/0148805 and/or U.S. Pat. No.8,133,345. For example, FIG. 16 illustrates an exemplary handle-heldextrusion-welding device 58 that may be used to extrusion weld sheets40, 44 of lining or liner material. In this example, the welding device58 is made up essentially of a hand-held drill serving as the drivesystem and removable attachment for this drill. In the attachment, astrand of thermoplastic material 60, supplied via one or several feedchannels from a feed device, is chopped up. The thermoplastic material60 is heated in a conveying device usually in the form of a wormconveyor and a plastering device so that the chopped thermoplasticmaterial 60 reaches a plastic state and is then expelled as weldingmaterial 66 through a welding chute of the welding device 58. The chuteincludes a degenerating device in the shape of an internal blower aswell as a heating device.

Accordingly, exemplary embodiments include extrusion welding thatcomprises heating and forcing out, under constant pressure andtemperature, the thermoplastic material 60. Infusing the thermoplasticmaterial 60 under the controlled parameters of constant pressure andconstant temperature over time helps reduce, minimize, or preferablyeliminate pinholes. Also in exemplary embodiments, the extrusion welder58 controls melt pressure and melt temperature with a display andcontrol box for convenient operation and monitoring. Because of thecontrolled pressure and temperature, the extruded thermoplastic material60 may thus fuse more material within the sheets than other weldmethods. With this automatic application of thermoplastic material 60under controlled parameters, a thicker, deeper, and stronger extrusionweld 62 may be created while also reducing, minimizing, or preferablyeliminating pinholes.

In exemplary embodiments, the thermoplastic material 60 may comprisepermanent thermoplastic lining materials such as, but not limited to,plasticized polyvinyl chloride, flexible polyvinyl chloride (F-PVC),rigid polyvinyl chloride, chlorinated polyvinyl chloride (CPVC),polyethylene (e.g., high molecular weight polyethylene (HMWPE),high-density polyethylene (HDPE), low-density polyethylene (LDPE),etc.), polyurethane/PVC alloy, synthetic rubber, fluoropolymer(homopolymer, copolymers (e.g., Poly(vinylidenefluoride-co-hexafluoropropene) (PVDF-HFP), etc.) or alloys),ethylene-chloro-tri-fluoro-ethylene (Halar ECTFE), geomembrane, ethyleneinterpolymer alloy (EIA), laminations of thermoplastic materials such asabove, etc.

Table 1 lists strength test results for a variety of weld locations forthe inventor's extrusion welds and prior art welds. The tests wereconducted on an Instron Model 1122 1,000 lb. load cell, wherein thewelds tested were used with Koroseal® material. In the table, the “base”refers to the stock material with no welds whatsoever. The “cornerextrusion weld” position refers to a welding for extrusion welding apair of side sheets. The “prior art weld” position refers toconventional or current welding processes, such as a strip weld process.As shown in Table 1, the inventor's welding processes result in higherweld strengths than the prior art welds.

TABLE 1 Failure Weld Load Strength Material pounds pounds Weld ThicknessTemperature per inch per inch Base 3/32 inch 70° F. 233 245 CornerExtrusion 3/32 inch 70° F. 228 228 Weld Prior Art Weld 3/32 inch 70° F.163 165 Base 3/16 inch 70° F. 485 414 Corner Extrusion 3/16 inch 70° F.324 317 Weld Prior Art Weld 3/16 inch 70° F. 306 227 Corner Extrusion3/16 inch 180° F.  135 98 Weld Prior Art Weld 3/16 inch 180° F.  78 54Butt Weld 3/16 inch 70° F. 405 397

In exemplary embodiments, sheets, panels, or walls of liner or liningmaterial may be cut from a roll of material, such as plasticizedpolyvinyl chloride (PVC) sheet membrane, or other preferably chemicallyinert material, etc. An example material that may be used for a liner orlining is a material sold under the brand name Koroseal® or HighPerformance Koroseal® manufactured by R.J.F. International Corporation.Other exemplary materials that may be used for a liner or lining includeAnchor-Lok® thermoplastic lining material from ATLAS Minerals andChemicals, Inc., or T-Lock® or Arrow-Lock® from Ameron ProtectiveLinings, or Exceline from F.C. Witt Associates Ltd. In yet otherembodiments, a liner or lining may comprise various other materials,such as rigid PVC type 1, rigid PVC type 2, vinyl or speciallyformulated flexible PVC, chlorinated polyvinyl chloride (CPVC),polypropylene (PPL), copolymer polypropylene (CoPPL), fiberglassreinforced plastic (FRP), polytetrafluoroethylene (PTFE), ethylenechlorotrifluoroethylene copolymer (ECTFE), polyvinylidene fluoride(PVDF), rubber, geomembrane, ethylene interpolymer alloy (EIA), etc. Insome exemplary embodiments, the sheets of a liner or lining may includefull-size RF (radio frequency) welded and/or overlapping extrusionwelded high performance Koroseal® panels (e.g., Koroseal® flexible PVCsheets, etc.), which helps eliminate lining seams in tank walls andbottom.

Exemplary embodiments disclosed herein may provide a vessel for storing,processing, transferring, and/or conveying liquids (e.g., storage orprocess tanks, immersion tanks for plating or coating processes, pits,gravity feed conduits for transferring or conveying liquid, etc.), whichcombines advantages of loose liners with those of adhered linings. In anexemplary embodiment, a vessel includes a type II PVC frame with fullbottom plate includes full-panel, high performance Koroseal® sheets thatare joined by extrusion welding and with mechanically fastened perimeterwelds. In this example, the vessel is configured so as to avoid bothtemperature limits and added costs of an adhesive bonded lining, yet hasits perimeter welds anchored to a solid frame structure for lastingperformance.

Exemplary embodiments of the inventor's liners and linings include weldsthat are formed with extrusion welding machines such that the welds arepreferably designed to eliminate gaps resulting from imperfect handwelded seams. The hot gas/hot air extrusion welding machine techniquesovercome disadvantages that are characteristic of hand-welding, such aschannels, pinholes, and gaps that can form behind hand welded seams andallow the solution in a tank, pit, trench, canal, drain, or other liquidcontainment vessel, etc. to flow behind the liner or lining and corrodethe substrate if a leak occurs. The inventor's techniques modify thepreheating process and delivery of the weld material. For example, awelding machine extrudes a high-performance, plasticized PVC weldmaterial that infuses into the substrate's pores and voids as well asjoins the PVC sheets that form the liner. Rather than extending thesheets, panels, or walls of liner or lining material, the sheets areconfigured or shortened to leave a relatively small gap at the joints orcorner intersections. This allows molten thermoplastic weld material toflow into and fill the gap between the sheets. Molten thermoplastic weldmaterial may also penetrate the joint or interface between the liner andframe (e.g., drywall corner beads, plastic frame, wooden frame, etc.).Or with a lining, molten thermoplastic weld material may penetrate thejoint or interface between the lining and tank. If the extrusion weldingis performed while the liner or lining is within a tank, moltenthermoplastic material may flow and reach the tank walls. In which case,molten thermoplastic material may remediate and repair the tank such asby filing crevices, etc. if the tank walls are corroded.

Molten thermoplastic weld material flows around portions of mechanicalfasteners, which fasteners are anchored (e.g., fastened, attached, etc.)to the frame or tank. This creates infused weld areas such that the weldareas and sheets of liner or lining material are anchored in the cornersas the mechanical fasteners are anchored to the frame or tank and theextrusion welds are anchored (e.g., held, retained, etc.) by themechanical fasteners. The infused molten thermoplastic material alsohelps eliminate channels, pinholes, and gaps behind the weld seams,which, in turn, helps reduce the probability of leaks, and helpsincrease the service life of the tank, pit, storage vessel, a gravityfeed conduit (e.g., concrete trench, canal, or drain, etc.) fortransferring or conveying liquid, etc. Should a leak happen, the weldhelps block solution from flowing behind the liner or lining.

Also with the inventor's hot gas/hot air extrusion welding machinetechniques the welding rod may be fully melted, which results in ahomogenous weld with fewer stresses. The weld may be formed in a singlepass, further reducing stresses introduced by the multiple passes commonin traditional hand welding. The inventor's extrusion welding is fasterand is less sensitive to surface oxidation.

As recognized by the inventor hereof, the inner bottom corners wherethree intersecting sheets must be joined are typical problem areas and afrequent source of early leaks and premature failures with conventionallinings in that it is difficult to perform a high-quality weld in acorner. This is because high-quality welds need the right speed,temperature, and pressure as the welding machine is moved along thejoint. But at a corner, the sheets can't be preheated because thewelding machine stops. The inventor's molded thermoplastic cornerinserts enable the welding machine to weld continuously in the cornerswithout having to stop at the corners of the frame-anchored liners.Accordingly, exemplary embodiments of the inventor's liners and liningsmay further include molded corner inserts in the corners as disclosed inU.S. Published Patent Application 2012/0148805 and/or U.S. Pat. No.8,133,345.

In some exemplary embodiments in which a liner or lining is intended fora large tank, the liner or lining may include full-size RF (radiofrequency) welded and/or overlapping extrusion welded high performanceKoroseal® panels (e.g., Koroseal® flexible PVC sheets, etc.) toeliminate seams. For example, if a tank is very large, a liner or liningmay include large sub-panels joined by skived edges with overlappedextrusion welds. This, in turn, may help avoid entrapped air, similar torubber joints, and eliminate hand welds with seam strips in immersionservice.

Exemplary embodiments of the inventor's liners may be used with varioustypes of tanks, including tanks intended for different uses, differentsizes and shapes, formed from different materials (e.g., steel,fiberglass, rubber, lead, plastic, wood, recycled composite wood, etc.),different types of vessels, tanks, or conduits (e.g., process tanks,indoor or outdoor containment pits, gravity feed conduits (e.g.,concrete trench, canal, or drain, etc.) for transferring or conveyingliquid, other storage or liquid containment vessels, etc.), etc. By wayof example, a liner or lining disclosed herein may include one or moreside sheets bonded to the corner sheets by welds (e.g.,butt-weld/infused weld, etc.). Multiple side sheets may be bonded andwelded along any particular side of the liner or lining depending on therelative size of the sheets to the tank in which the liner or liningwill be used. As the tank may have a substantially tall height,ascending rows of corner sheets and side sheets may be also be bonded bywelds. Also the sheets may have a rectangular configuration or differentconfiguration. The size and shape of the sheets may be configured (e.g.,cut, etc.) to match the interior surface of a tank in which the liner orlining will be used. Because the sheets may contract and expand slightlyin width during installation operations and during use due to thermalexpansion and contraction, the sheets may be oversized to allow for suchdimensional changes. In an exemplary embodiment, the thickness of thesheets may be about 3/32 inches. In another exemplary embodiment, thethickness of the sheets may be about 3/16 inches. These dimensionsdisclosed in this paragraph (as are all dimensions disclosed herein) areexample in nature as other exemplary embodiments of a liner or liningmay be sized dimensionally larger or smaller depending on the tank towhich they will be applied.

Exemplary embodiments may be configured to be used as relatively rigid“drop-in” liners, which may possess superior perimeter machine welds andwhich may be mechanically anchored to a frame or framework for placementinto a tank. In such exemplary embodiments, the frame-anchored liners donot float in the tank as do some bag liners. The frame-anchored linersmay also allow reductions in costs and downtime as compared to someconventional lining bonding methods as the inventor's frame-anchoredliners may be installed and positioned within a tank without having tofirst prep the tank's interior surface and/or without having to removean existing lining, if there is one. For example, an exemplaryembodiment of the inventor's liner may be installed or “dropped in” atank without having to blast, grind, prime, apply adhesive, etc. to theinterior of the tank as is required for some conventional linings.

Exemplary embodiments of the inventors' frame-anchored liners may beinstalled in or added to used tanks of steel, fiberglass, rubber, lead,plastic, etc., whereby the liner restores the used tank to equal orbetter than original condition and/or increases the service life of theused tank. The inventor's liners may also allow new tanks to beconstructed of lower cost materials, e.g., recycled lumber, plywood,alternative building components, etc. as the inventor's liners wheninstalled provide a corrosion barrier between the tank walls and thecorrosive contents stored within the tank. In an exemplary embodiment,the inventor has disclosed a frame-anchored drop-in free-standing linerthat may be installed in a tank made of wood, plastic lumber, compositewood, etc. whereby the liner provides good corrosion resistance insidethe tank and exterior steel corrosion is no longer an issue for theexterior of the non-steel tank. Spark testing and leak detection arealso available with exemplary embodiments of the inventor's liners andlinings disclosed herein.

Exemplary embodiments (not shown) of a lining or liner may furtherinclude an absorption layer or impact absorbing bumper pad positionedover and/or bonded to the top of the bottom sheet. This impactprotective layer may comprise a honeycomb, egg-crate, and/or laminatestructure, such as a non-float (high specific gravity) thermoplastic.The structure may also comprise compressible material that absorbsimpact from dropped parts. By being made of pieces of a size and weighteasily handled by installation personnel, this structure is easilyremoved from the tank bottom if a lining or liner repair on or near thebottom is required.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail. In addition, advantages and improvements that maybe achieved with one or more exemplary embodiments of the presentdisclosure are provided for purpose of illustration only and do notlimit the scope of the present disclosure, as exemplary embodimentsdisclosed herein may provide all or none of the above mentionedadvantages and improvements and still fall within the scope of thepresent disclosure.

Specific dimensions, specific materials, and/or specific shapesdisclosed herein are example in nature and do not limit the scope of thepresent disclosure. The disclosure herein of particular values andparticular ranges of values for given parameters are not exclusive ofother values and ranges of values that may be useful in one or more ofthe examples disclosed herein. Moreover, it is envisioned that any twoparticular values for a specific parameter stated herein may define theendpoints of a range of values that may be suitable for the givenparameter (the disclosure of a first value and a second value for agiven parameter can be interpreted as disclosing that any value betweenthe first and second values could also be employed for the givenparameter). Similarly, it is envisioned that disclosure of two or moreranges of values for a parameter (whether such ranges are nested,overlapping or distinct) subsume all possible combination of ranges forthe value that might be claimed using endpoints of the disclosed ranges.In addition, disclosure of ranges includes disclosure of all distinctvalues and further divided ranges within the entire range.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. For exampleand for descriptive purposes only, the term “liner” may be used hereinto refer to a free standing liner (e.g., drop-in liner, etc.) for a tankwhere the liner is not or will not be adhesively bonded directly to thetank's walls and bottom. As another example, the term “lining” may beused herein to refer to a lining for a tank where the lining will be oris adhesively bonded directly to the tank's walls and bottom. Fordescriptive purposes only, the terms “liner” and “lining” may also beused interchangeably herein when describing some embodiments

As used herein, the singular forms “a,” “an,” and “the” may be intendedto include the plural forms as well, unless the context clearlyindicates otherwise. The terms “comprises,” “comprising,” “including,”and “having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items. The term “about” when applied to valuesindicates that the calculation or the measurement allows some slightimprecision in the value (with some approach to exactness in the value;approximately or reasonably close to the value; nearly). If, for somereason, the imprecision provided by “about” is not otherwise understoodin the art with this ordinary meaning, then “about” as used hereinindicates at least variations that may arise from ordinary methods ofmeasuring or using such parameters. For example, the terms “generally”,“about”, and “substantially” may be used herein to mean withinmanufacturing tolerances.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

What is claimed is:
 1. An apparatus for lining a liquid containmentvessel, the apparatus comprising at least one sheet anchored to at leastone structural component by an extrusion weld and at least onemechanical fastener that is coupled to the structural component, whereinthe extrusion weld comprises thermoplastic material encapsulating atleast a portion of the at least one mechanical fastener, wherein themechanical fastener comprises a bent pin, a stud weld, and/or a hollowportion in which a portion of the thermoplastic material has infused,whereby the sheet is anchored to the structural component.
 2. Theapparatus of claim 1, wherein the mechanical fastener comprises thehollow portion in which the portion of the thermoplastic material hasinfused.
 3. The apparatus of claim 2, wherein the mechanical fastenercomprises at least one threaded mechanical fastener having spaced-apartthreads defining the hollow portion and between which the portion of thethermoplastic material has infused.
 4. The apparatus of claim 2, whereinthe mechanical fastener comprises a head having a tool reception slotdefining the hollow portion in which the portion of the thermoplasticmaterial has infused.
 5. The apparatus of claim 1, wherein: the liquidcontainment vessel comprises a pit or trench; and the structuralcomponent comprises at least one concrete sidewall of the pit or trenchto which the sheet is anchored by the extrusion weld and the mechanicalfastener.
 6. The apparatus of claim 5, wherein: the mechanical fasteneris adjacent or extends through an upper edge portion of the sheet; andthe thermoplastic material is along an interface between the upper edgeportion of the sheet and the concrete sidewall.
 7. The apparatus ofclaim 6, wherein the mechanical fastener and the upper edge portion ofthe sheet are within a notched portion of the concrete sidewall.
 8. Theapparatus of claim 1, wherein: the sheet comprises a geomembrane and/oran ethylene interpolymer alloy (EIA); and/or the thermoplastic materialcomprises a geomembrane and/or an ethylene interpolymer alloy (EIA). 9.A lining comprising the apparatus of claim 1, wherein the sheet and asecond sheet are anchored by the mechanical fastener that is coupled tothe structural component within a gap between the sheet and the secondsheet and by the extrusion weld that is coupled to the mechanicalfastener, wherein the thermoplastic material fills the gap between thesheet and the second sheet.
 10. The lining of claim 9, wherein: thesheet and the second sheet comprises a geomembrane and/or an ethyleneinterpolymer alloy (EIA); and/or the thermoplastic material comprises ageomembrane and/or an ethylene interpolymer alloy (EIA).
 11. A liningcomprising the apparatus of claim 1, wherein the structural componentcomprises a tank, an outer shell, or a frame to which the sheet and asecond sheet are anchored by the mechanical fastener that is coupled tothe structural component within a gap between the sheet and the secondsheet and by the extrusion weld that is coupled to the mechanicalfastener, wherein the thermoplastic material fills the gap between thesheet and the second sheet.
 12. A liquid containment vessel comprising aplurality of sheets, at least one pair of adjacent sheets joined by anextrusion weld along an interface between the pair of adjacent sheets,and at least one mechanical fastener coupled to at least one structuralcomponent within or adjacent to a gap between the pair of adjacentsheets, wherein the extrusion weld comprises thermoplastic materialencapsulating at least a portion of the at least one mechanicalfastener, wherein the mechanical fastener comprises a bent pin, a studweld, and/or a hollow portion in which a portion of the thermoplasticmaterial has infused, whereby the pair of sheets is anchored to thestructural component.
 13. The liquid containment vessel of claim 12,wherein the mechanical fastener comprises the hollow portion in which aportion of the thermoplastic material has infused.
 14. The liquidcontainment vessel of claim 13, wherein the mechanical fastenercomprises at least one threaded mechanical fastener having spaced-apartthreads defining the hollow portion and between which the portion of thethermoplastic material has infused.
 15. The liquid containment vessel ofclaim 13, wherein the mechanical fastener comprises a head having a toolreception slot defining the hollow portion in which the portion of thethermoplastic material has infused.
 16. The liquid containment vessel ofclaim 13, wherein: the liquid containment vessel comprises a pit ortrench; and the at least one structural component comprises at least oneconcrete sidewall of the pit or trench.
 17. The liquid containmentvessel of claim 13, wherein: the sheets comprises a geomembrane and/oran ethylene interpolymer alloy (EIA); and/or the thermoplastic materialcomprises a geomembrane and/or an ethylene interpolymer alloy (EIA). 18.An apparatus for lining a liquid containment vessel, the apparatuscomprising at least one sheet anchored to at least one structuralcomponent by a weld and at least one mechanical fastener that is coupledto the structural component, wherein the weld comprises materialencapsulating at least a portion of the at least one mechanicalfastener, wherein the mechanical fastener comprises a bent pin, a studweld, and/or a hollow portion in which a portion of the material hasinfused, whereby the sheet is anchored to the structural component. 19.The apparatus of claim 18, wherein: the mechanical fastener comprisesthe hollow portion in which the portion of the material has infused;and/or the weld is an extrusion weld comprising thermoplastic materialencapsulating at least a portion of the at least one mechanicalfastener.
 20. The apparatus of claim 19, wherein: the mechanicalfastener comprises at least one threaded mechanical fastener havingspaced-apart threads defining the hollow portion and between which theportion of the material has infused; and/or the mechanical fastenercomprises a head having a tool reception slot defining the hollowportion in which the portion of the thermoplastic material has infused.21. The apparatus of claim 18, wherein: the sheet comprises ageomembrane and/or an ethylene interpolymer alloy (EIA); and/or thematerial comprises a geomembrane and/or an ethylene interpolymer alloy(EIA).
 22. A lining comprising the apparatus of claim 18, wherein thesheet and a second sheet are anchored by the mechanical fastener that iscoupled to the structural component within a gap between the sheet andthe second sheet and by the weld that is coupled to the mechanicalfastener, wherein the material fills the gap between the sheet and thesecond sheet.